Switch machine



Nov. 17, 1953 N. C. L. BROWN l +V e e h S S +v e e h S 5 E f N I H Mv M .H C T I W S 9 A. 9 1 4 2 c. e D d e l .l F

Nz/ n. m WTA.; Tm m.: w 621 .NM2 um n md n m m \OH :l .s cd2/wl m ZD E i .maui

N. C. L. BROWN Npv. 17, 1953 SWITCH MACHINE 5 sheets-sheet 2 ,Filed Dec. 24, 1949 :inventor Gttorneg um G mm EN Nov. 17, 1953 N. c. BROWN 2,659,812

SWITCH MACHINE Fiied Deo. 24; 1949 svsheets-sheet s 65j I|c.4. Y e@ 65h 11o loI I l I To SIGNAL I eovERmNGII-V I 10o/I@ 65s ovER swm: |654 101 I l f IN RsvERsE I I` I 5 PosmoN Isg I 5I I g3 To srNAL I I I euvel-mme L/ I I IM* Il @5b ovER SWITCH 111 1N No1-1MAL p I I I II POSITION I I l I I I l I I I I I I Ie l I l l I I I I II l I I I I l 'l I I I: l I III|||||||IIII I I IOZ l I Y I l I I l I I I s4 I I I III l IIIIlIlIIh' 73 I I 74 I I I 61 I I z I I 69 I ez 68 I Ix :Inventor 89 wm. m,

33 GIIorneg Nov. 17, 1953 N. c. L.. BROWN SWITCH MACHINE Filed Dec. 24, 1949 5 Sheets-Sheet 4 INVENTOR. 72. C. @www H15 ATTORNEY Nov. 17, 1953 N. C. L. BROWN SWITCH MACHINE Filed DeC. 24, 1949 FIG. 8.

5 Sheets-Shea?I 5 H15 ATTORNEY.

Patented Nov. i7, 1953 SWITCH MACHINE Ned C. L. Brown, Scottsville, N. Y., assigner toV General Railway Signal Company, Rochester,

Application December 24, 1949, Serial No. 134,969

13 Claims. (Cl. 246-240) This invention relates to switch machines for railroads, and it more particularly pertains to improvements in electric switch machines and their connections to associated track switches.

One of the problems encountered in railway practice involving the use f power switch machines for the operation of track switches is to lock facing switch points against the possibility Of their being operated by extraneous means such, for example, as by vibration due to the passage of trains. Another problem encountered in switch yards and similar places where frequent switch movements are made is to prevent damage tothe track switch and/or its associated switch machine in case the track switch is inadvertently trailed when in the wrong position for such trailing movement.

An object of the present invention is to provide an improved means for connecting a switch machine to a track switch whereby an attempt to spread a closed switch point by vibration or A other forces applied to such switch point is resisted by a toggle like locking connection of the switch point to the switch machine.

Another object of the present invention is to lock the closed point of a track switch through a novel means of connection of the respective switch points to the switch machine, and by use of separate throw rods for the respective switch points to provide means governed by the character of the connection of the switch to the switch machine for unlocking the closed point in response to the approach of a train trailing the track switch when such switch is in the wrong position for such train movement, and thereby prevent damage to the track switch and/or switch machine.

Another object of the present invention is to provide an improved operating mechanism for a switch machine wherein a variable torque friction clutch permits slippage in case of an obstruction of the switch points in mid-stroke to allow parts of the machine to operate through a predetermined complete cycle and pole change the switch machine motor to condition the machine for operation in the opposite direction.

.Another object of the present invention is to provide an improved switch locking and point detector contact mechanism wherein yieldable locking dogs are employed to permit the switch machine to complete its operating cycle, even though the track switch lock rods may be out of alignment so that they cannot be locked.

The novel features of this disclosure involv-V ing a railway switch operating and locking mechanism have been claimed herein; whereas,

the novel features of the switch locking mechanism per se disclosed herein have been claimed in my divisional application Ser. No. 373,473, led August 11, 1953.

Other objects, purposes and characteristic features of the present invention will be in part obvious from the accompanying drawings, and in part pointed out as the description progresses.

In describing the invention in detaily reference is made to the accompanying drawings in which similar reference characters are used to designate corresponding parts throughout the several views, and in which:

Fig. 1 is a plan view of a switch layout showing a single track switch and switch machine organization according to one embodiment of the present invention;

Fig. 2 is a plan View of the switch machine of Fig. 1 with its cover removed and certain parts shown in cross section;

Fig. 3 is an elevational sectional view of the switch machine as viewed along the line 3 3 of Fig.2;

Fig. 4 is an expanded view in perspective of parts of the switch machine involving clutch and circuit controlling apparatus; Y

Fig. 5 is a plan view of a switch layout showing a modied form of single track switch machine organization;

Fig. 6 is a plan view of acircuit controller and locking mechanism employed in the switch machine as shown in Fig. 5;

Fig. 7 is an elevational view shown partially in cross section of the switch point detector and locking mechanism of the switch machine as shown in the switch layout of Fig. 5;

Fig. 8 is an elevational view of the point detector and locking mechanism as taken along the section line 8--8 of Fig. '7; and,

Fig. 9 is a plan view of the point detector and locking mechanism as taken along the section line 9--9 of Fig. '7.

With reference to Fig. 1, a switch layout is illustrated as one embodiment of the present invention wherein conventional long switch ties numbers 0 and 2 are provided for the mounting of the switch machine SM at its ends, and a shorter intermediate tie number 1 is employed as a support for the right-hand side of the switch machine SM as viewed in Fig. 1. The ties are held in proper spaced relationship by the tie straps l0 and i I which are suitably secured near the ends of the ties as by the lag screws I2. Tie plates are preferably provided on the top of the switch ties extending throughout their entire lengths as a means for accurately maintaining the gauge of the rails at the track switch, and as a means for helping to maintain the switch machine SM a fixed distance from the switch points. Slide plates I3 are provided beneath the stock rails I4 and I5 and the movable switch points Iii and Il respectively in the usual manner.

The switch machine SM of Fig. 1 is secured to numbers 0, l and 2 ties respectively by suitable bolts or lag screws I8, it being secured to the number tie at its rear end as viewed in Fig. 1,J to the number 2 tie at its front end, and to the number l tie at its right-hand side. in practice, the number 2 tie can be a long and deeper tie with a portion hollowed out for clearance of the lower portion of the switch machine SM. Under such conditions, both sides of the switch machine SM are secured to the number l tie.

Connection of the switch machine SM of Fig. l to the respective switch points is accomplished by the respective throw rods I9 and 20, the throw rod I8 being effective to connect the near point I6 of the track switch to the switch machine SM, and the throw rod 2G being effective to connect the far point I'I of the track switch to the switch machine SM.

With reference to Figs. l, 2 and 3, the major portion of the switch machine operating mechanism is housed in a suitable case C, preferably of cast iron, which is provided with a cov-er 2| having a suitable channel about the periphery of its edge for receiving cording 22 or other suitable packing material for insuring a tight fit of the cover to the case C. The cover is securely held in position by suitable hasps (not shown) and locked in accordance with the requirements of practice.

The front and back ends of the case C as viewed in Fig. 1 have secured thereto suitable mounting brackets 23 and 24 respectively which in turn are secured to the respective switch ties Nos. Zand 0. The bracket 2li is illustrative as being secured to the case C by the bolts 25 which secure an upright portion 2da. of the mounting bracket ,2Q to a. suitable boss 2 on the rear end of the case C. The front mounting bracket 23. is bifurcated in its portion extending to the case C so as to allow clearance for the respective crank arms of a throw crank 2S which has a structure andA mode of operation to be hereinafter considered. lIhe bifurcated portions 23a and 23h of the mounting bracket 23 are suitably secured to bosses 3l on the case C by the bolts 32. It is to be understood that other forms of supporting brackets, may be employed, and that other means, such as welding can be employed for securing the mounting brackets to the case C in accordance with the` requirements of practice.

A hollow throw shaft 33 (see Fig. 2) extends longitudinally through the switch machine substantially parallel to the stock rails. The shaft 33 is driven by the motor M through suitable re duction gearing and a variable torque clutchrin a-manner to be hereinafter more speciically described. The throw shaft 33- is suitabl-y supported in the switch machine by three-bearings, one of which is formed in the front portion of the mounting bracket 23 at the point Se, another of which is formed in the front end ofthe case C at the point 35, and another of which is formed at the point 36 in a bearing supporting bracket 31 which is suitably secured substantially at the center of the case C Vto the bottom of the case by` the bolts 38. Although. specificallyxv these If desiredA bearings are illustrated as being formed in the castings, it is to be understood that brass or bronze bushings may be employed, or ball or roller bearings in accordance with the requirements of practice.

The crank 28 is keyed to the throw shaft 33 in a position between the shafl-J bearings Sil and 35 and between the bifurcating portions 23a and 23h of the mounting bracket 23. This crank 23 has formed thereon the respective crank arms and 4Q which are displaced substantially 90 from each other as illustrated in Fig. 3. It is to these crank arms that the throw rods I9 and 2i? for the respective switch points I6 and Il' are secured. The rods I9 and. 2B are connected to the respective switch points I5 and Il by suitable hinge switch clip ttings 3, and they are connected between thev jaws of the respective crank arms 33 and by the pins 4I and cotter pins :l2 (see Figs. 2 and 3) A threaded portion of the ends of the rods I9 and 2i) permits va fine adjustment of the closure of the switch points I6 and Il.

The drive motor M (see Fig. 2) is suitably secured within the case C at the right hand side of the case, and such Imotor M, when energized by a suitable circuit organization such as is shown in Fig. 4, drives with its pinion 133 the reduction spur gears 4, t5, and 6B, the gear 46 in turn being effective to drive a ring gear 137 of the variable torque clutch. The gear lill is pivoted on a shaft 138 which is journaled atv one end in the boss i9 in the front end of the-case C and at the other end by the bearing support 37 at the point 5S. Similarly the gear .6 turns about a pivot shaft which is journaled at the` point 5I in the front end of the case C and at the point 52 in the bearing support 3l. The intermediate gear i5 coupling the gears ifi and lois pivoted on the throw shaft 33, but is not secured thereto, the gear i5 having front and back end bearing points 53 and 54 respectively.

The clutch organization as shown in Figs. 2 and 4 comprises in general a cylindrical drum S3 freely rotative about the shaft 33 and driven by the ring gear @l which is cut on the outer circumference of the drum Se, or which maybe a separate` ring gearpressed or otherwise fitted onto the drum 6E) according to the requirements of practice; a cylindrical clutch shoe GI having frictional engagement with the inner cylindrical surface 62 of the drum 6G; two cranks i3 and lfi pivoted to rotate freely on the shaft 33 within the shoe and biased awayv fromY each other by a spring *I5 as a means ifor governing'the -cation of pressure of the shoe against the inner cylindrical surface t2 of the drum 60; a circular bearing plate te; an endY plate S5 keyed to the shaft 33 and a spring biased coupling yoke Gt for normally coupling the end plate 65 and the bearing plate Sli as a means for normally driving the throw shaft 33 in accordance with the output of the clutch.

To consider the structure of the respective parts of the clut-ch more specifically, with reference to Fig. 2, the drum 3c has a lower bearing 6l which is freely rotative on the throw shaft 33. The upper edge of the drum 6G as viewed in Fig. e is stepped to a smaller outside diameter for providing a shoulder 58 forYsup-port of the pole changer ring spaced from the end plate which bears against the upper edge 69A of the drum The clutch shoe 6I is preferably of resilient sheet metal with an outer friction lining as a suitable friction surface for bearing against the inner cylindrical surface 62 of the drum 69. The

acsasia" 5, shoe 6| has its left-hand side open for approximately 30, although the extent of the open portion is not at all critical, provided the other cooperating parts of the clutch are correspondingly constructed. Suitably secured to the open ends of the clutch shoe and extending elevationally as viewed in Fig. 4, are respective normal and reverse clutch output driving detents 'l0 and li which extend upwardly within an annular slot l2 in the bearing plate 64.

The clutch shoe 6| is tted within the drum 59, and it is expanded against the inner surface 92 of the drum $0 by action of cranks 'I3 and lll which are biased apart by a compression spring '55. The cranks 13 and 'I4 are freely pivoted on the shaft 83, and their crank arms 'I6 and have respective shoulders 18 and 19 formed at their ends to engage the outer edges 8D and 8| of the detents 1| and 'l0 so as to normally expand the clutch shoe 6| in accordance with the compression of the spring l5 which is suitably disposed between the respective inner faces of the crank arms 'i5 and 11. The bearing plate 54 ts within the upper edge of the drum 68 as viewed in Fig. 4, and thus serves as a bearing for the upper end of the drum 60. In this position, the detents lil and 1| of the clutch shoe 6| extend upwardly through the annular slot 12 in the bearing plate 64 and thus cause rotation of the plate 64 relative to the rotation of the clutch shoe 6 i.

With reference to Fig. 2, the circular end plate 55 has its hub 82 keyed to the throw shaft 33 by the key 83, and the extension of the hub 82 of the end plate 55 downwardly as illustrated in Fig. 2 provides a pivot for the bearing plate 64, although it will be readily apparent that the bearing plate 54 can be pivoted directly on the throw shaft 33 if desired.

A pole changer ring 84 (see Fig. 4) is provided of a diameter to iit into the step of the drum 50 against the shoulder 68. The outer edge of the pole changer ring 84 (see Fig. 4) is recessed for a portion comparable to the number of degrecs of rotation of the throw shaft 33, which is assumed for this embodiment of the present invention to be approximately 120. Thus the respective ends 85 and 86 of the recess 81 dene the respective ends of the stroke of the switch machine, the end 85 being associated with the normal position of the switch machine according to this embodiment of the present invention and the opposite end 86 being associated with the reversed position. As a means for rotatively coupling the pole changer ring 84 to the drum 58, location pins 88 are secured to the ring 84 and extendk downwardly therefrom as viewed in Fig. 4 so as to engage holes 89 in the shoulder 58 'of the drum 68. The pole changer ring is suitably biased against the shoulder 68 so as to maintain its pins 88 in engagement in their associated registration holes 89 by a suitable crimped spring washer 9|.) (see Fig. 2) which is maintained under compression between the upper surface of the pole changer ring 84 and the lower surface of the end plate 65.

Although it is to be understood that various forms of contact actuated mechanisms can be employed in the circuit controller, the pole changer contacts 9| and 92 are illustrated in Fig. 4 of this embodiment of the present invention as being actuated by a toggle rocker arm which comprises a U-shaped structure 93 carrying rollers 94 and 95 at the respective ends of the structure which are actuatedby the recess ends;l 85

6 and 86 respective of ring 84. The rollers 94 and 95 are actuated by the respective normal and reverse ends and 85 of the recess 8l, and the actuation of the toggle under either of these conditions deenergizes the switch machine motor M in a manner to be more apparent as the The periphery of the circular end plate 55 is used as a cam surface for actuation of a roller of a circuit roller operating arm which is illustrated in Fig. 4 diagrammatically as actuating circuit controller contacts which are closed only in the respective full normal and full reverse positions of the track switch. These contacts are generally used in signal control circuits for governing the signals either directly, or indirectly through the selecting of line circuits in accordance with the requirements of practice. The recess 65a in the outer edge of the end plate 65 receives the roller when the track switch is in its normal position as illustrated in Fig. 1. When the track switch is operated to its reversed position, the roller rides on to the detent 65h in the outer edge of the end plate 55 and thus actuates the associated contact to its left end position to close one or more circuits for governing signals over the track switch in its reversed position.

The yoke 58 has downwardly extending pins |89 normally engaging the end plate 55 and the bearing plate 64 by extending through registering holes |0| and |92 in these respective plates. It is therefore provided that rotation of the bearing plate 64 as provided by the output of the clutch is applied to the end plate 55 which is keyed to the throw shaft 33, and thus rotation of the bearing plate 84 causes rotation of the throw shaft 33. The connecting yoke 86 is biased in its engaging position by a spring |03 as shown in Fig. 2 which is maintained under compression between the case C and the yoke 55, such spring being maintained in longitudinal alignment by bosses |84 and |85 in the case and the yoke respectively. Because of the connecting yoke 65 extending across the end of the `throw shaft 83 as is illustrated in Fig. 2, by use requirements of practice.

With reference to Fig. 3 it will be noted that the respective throw rods I9 and 20 are formed with a substantially 90 hook near the point of connection of the rods to the respective crank arms 39 and 48. It is by this arrangement that the switch points when closed are locked against the possibility of their being opened by vibration, or by the application of a force tending to separate the switch points from their closed posiacogerse Itis thereforedesirable that the left-.handend of the switchu'od [SiV be curved substantially asv is. shown inFig; 3 so that with the switchn1a-I chine, SM; in its normal posi-tion .as shown, the. switchrod; i9; is wrapped tightly about therlower portion of the peripheryot theVcrank-Zpfto securely look the. normal switch point 61 in its Closedrositil.

Towconsider the mode of operation ofv the.

switch machine organiza-tion, it will be assumed that the control switch SML (seeFig. 4) isae-` tuated. t its rientri-aard. position for causing. the tract Stth to be. Operated. t0. its. reverse position, By this actuation a circuitV is closed for theenerslationof the switch machine motor.

M extending. from the. positiv@ terminal of. the blltery l. and including safety contact selections.- indieaied by the leiter Contact It?. of the. Switch SML. 11.1 its righi-hand essi-tion 09e.- tact 9.2 of the) pole changer circuit controller in its lower position, karmature A of the motor- M,

contact Sli ci'l the 'polefchanger circuit controller tuationof thedrurn @Eloi the clutchinva counter. clockwise direction actuates the. detent Hv (see.

Fig. 4i) against the upper` end ofthe` annular slot Elin thebearing plate Sii andthrcugh. this en,- gagernent of thedetent i i. with. the bearing plate iid drives. the throw shaft 33 in a counter-clockwise direction. With reierencetoFig.` 3, therotation of the shaft 33 in acounterclockwisedi-r rectionv is eiective to unhook the throw rod I9 from thebaci; of the throw shaft 33 andto. ac-

tuate thethrow rodii to its right-hand position. to start the closing of the Switchpointt i] against..

the stock rail E5.

The counter-clockwise rotation` of the. shaft.,

33n .continues untilthe pole. changer toggle 93, is actuated by the roller (see Figl 4) striking lthe end 8670i the recess jrthewpolo changer ring es, at which time the toggle s3 is actuated to its. left-hand actuated position and thus thecircut.

just clsscribedior the inotor. armaturen and the rnotor eld F are opened' atcontacts 3i and 92 of the pole changing circuit controller, Thus thernotor M is deenergized at the end. of the stroke and the shifting or" the pole changer contacts 9! and 92 to their upper positions condif. tions a circuit for the motor M so that upon.

subsequent actuation of the switch control lever SML to its left-hand position, energy can. beapplied to the motor M of a polarity to restore thev switch machinelto its normal, position,

The stroke of operation of the track switch in With the...switch machine andthe track 8 itsloperationromits. normal. to its reverse. pos i. tion isiassumed to. besuch asV to actuate pin 4I (seeFig. 3); connecting the throw rod 20 to the crank'armtoha position whereby it is slightly above a line thatcouldrbe drawn from the center .ot that pinA tothe switch point I'I with the rod 2i! hooked-tightly under the portion 23h of the bracket 2;3as. thenorrnal rod I9 is hooked around the crank :2-8 w.ith the switch machine in its normal position. Thus a hook lock is provided for loclgingthe. switch point Il' against the stock rail i5` because any force exerted to urge the switch-*point I1; awayfrom such stock rail is appliedto urgetherod 2|);toY be more tightly hooked underthev portion 23h of the bracket 23.

It is preferable that the switch rods be adjustedA so. that 4the. switch pointsy are actuatedV tightlyagainst their-1A respective stock rails just prior to `the.,rotation ofthe cranks to which they are. .connected totheir full locking positions. With the switch point closed prior to the completion` of rotation. of the shaft 33 to its fully locked position, the switch rod connecting the closedpoint is sprung slightly in a manner readily absorbed by the hook portion ofthe rod so that when operation of theswitch machine has been cornpletedtto. the point where the motor M is deenergizedthe.particular switch point that is closed is. urgedin thatl closed position by a spring tension(thatlisfstored;withinithe associated switch rod.

With. referenceto Fig. 4, assuming that it is desiredto actuate theltrack switch from its reverseto itslnorrnal. DQStQn, the control switch SML i s. acti1at ed to its.A lefthand position and thereby.V establishes. al. circuit for the motor M entending frontthepostiyeterminal of the battery ilfand including safety circuit contact selections as indicated bythe letter-X, contact I'i out the controlswitch. SML in its left-hand position, contactyjlI of the-pole changer circuit controller inits upper. position, armature A of the motor 11V', contact 92` of the pole changer switcht controller in its upperv position, and the iield winding. |018 ofthe motor M to the negative terminal otthebattery |06. It willbe noted that the.energization.of*the motor M by this last describedV circuit is of. the opposite polarity for the armaturen andkthersarne polarity for the ield I S. ascompared to, energization by the circuit formerly described for energization of the motor M# accordance with .the designation of a reversedy position for. the track switch. It is thus.

providedthatuin response to theactuation of the control SML to its leit-handv position, the motor Mjis energizedwith a polarity to turn its armature-andpinion 43j in a` clockwise direction and thus eiect the clockwisel rotation oi' the throw shaft 3 3 through the. gear reduction and the clutch organization. This operation continues untilthe toggle roller 9isee Fig. 4) hits the recess end andlactuates thecontaots Si and 92 to4 theird lower position to open the normal operating-circuit which, has been described.

To consider the mode of operation when the track-switch is split by atrailing train movement, it will be assumedetnat the track switch is locked in itsnormal position as illustrated in Fig. l, and itQwill-befurther assumed tha-t a train proceeds fIOm the turnouttrack to pass through the track switch.` WhenAtlie train progresses to a point of narrow gage Where the wheels of the train apply pressure against; the switch point I1, the reverse throw rod` @which isconnected to this Switch point. is actuated. to the right and thusV actsthroughthe crank arm l Which connects 9 the switch rod 20 to the throw shaft 33 to rotate the throw shaft in a counter-clockwise direction as viewed in Fig. 3.

This rotation continues as the train progresses through the switch, and because of the counterclockwise rotation of the throw shaft 33 the normally closed switch point I6 is unlocked from its hooked position around the hub of the crank 28, and thus this switch point can also. be crowded open as the train progresses through the track switch. It will be readily apparent that by both switch points being unlocked, the wheels of the train can crowd the switch points to a position to render free passage of the train between the switch point IS and the stock rail I4, and the switch point l1 will be crowded to a position where it will be closed against the stock rail l5, corresponding to the full reverse position of the track switch. It will thus be seen that the track switch can be trailed without damage to the track switch or to the switch machine SM.

To consider the operation of the switch machine under the above described trailing condition it will be apparent that as the throw shaft 33 is rotated in its counter-clockwise direction by tension applied to the throw rod 2t the. end plate 65 is rotated in a counter-clockwise direction as viewed from the throw rod endof the shaft 33, and because of such plate being coupled by the yoke te to the bearing plate 6A, the bearing plate Eid is also rotated in the same direction. The rotation of the plate 64 applies pressure to the engagement of the ends of the slot 12 with the detent ll of the brake shoe 6l so as to slip the clutch as the ratio of the reduction gearing of the switch machine is such as to substantially iock the clutch ring gear il against being driven by the throw shaft 33. The nature of the clutch is such as to allow a freer slippage in response to a sudden shock so that if the throw shaft is quickly rotated, the spring 'i5 is compressed during the acceleration of the throw shaft 33 as compared to the slippage of the brake shoe tl so that the brake shoe I clips more freely within the drum 62 under conditions where a more abrupt shock is applied to the throw shaft as by a train trailing the switch at a relatively high speed.

It will be noted that because of the slippage of the clutch throughout the entire stroke of the track switch as above described the pole changer ring 84 has become out of correspondence with the end plate 65, the end plate 55 being substantially in the reverse position and the pole changer ring 34 being maintained substantially in its normal position. The rotation of the endy plate 65 under such'conditions opens the circuits for signals closed through the contact H0 (see Fig. 4) in its right-'hand position because of the roller iii being forced out of the recess tre in the end plate. In all probability the forcing of the switch points to their reverse positions by passage of the train is not suiicient to complete the rotation of the end plate 65 to a position to actuate the roller lll by the detent 65D and thus close the circuits for controlling a signal governing trafiic over the track switch in its reverse position. Under such conditions, if the operator of the power switch is remote from the track switch so as to not have been aware of the improper movement over the switch by a train, he will become aware that something is wrong when he can no longer clear a certain signal over a particular position of the switch. The normal procedure is to then inform a maintainer that something is wrong and that the switch should be inspected.

To restore the ring 34 to a position in correspondence with the end plate 55, the operator of the track switch need only to actuate the Switch control lever SML (see Fig. 4) to its reverse operating position (right-hand position) so as to cause the driving of the pole changer ring Sd to the full reverse position of the switchmachine and thereby drive the switch point I1 to its fully locked position and to actuate the end plate G5 to its full reverse position so as to permit the closing of a signal control circuit through the switch circuit controller. After this completion of operation has been accomplishedy the switch y machine is conditioned for operation back to its normal position when operation to its normal position is called for because the pole changer contacts 9i and 92 are actuated to pole change the motor M and thus condition the motor for operation to its normal position when lever SML is actuated to its left-hand position in accordance with the usual mode of operation of the switch machine.

It will be noted that while driving the switch machine to its reverse position under the above assumed conditions, the switch points are already assumed to be nearly in their reverse positions, so there is little operation of the switch points as compared to full stroke operation of the switch machine SM. It is thus provided that the switch machine initially completes the operation of the switch points to their reverse positions, and when the points reach these positions, the throw shaft 33 is stopped in its rotation by the hooking of the switch rod 2t under the portion 23h of the bracket 23. When the rotation of the throw shaft 33 is suddenly stopped in this manner, additional pressure is momentarily applied through the plate t4, to the detent 'H (see Fig. 4) that is connected to the shoe El of the clutch and the compression spring 'l5 that is disposed between the cranks 'i3 and. 'M is compressed` thus removing a part of the expanding force that is normally applied to the clutch shoe 6| so as to Y permit the clutch to momentarily slip freer and to therefore soften the shock on the switch machine mechanism of the abrupt stopping of the rotation of the throw shaft 33.

By requiring the drive of the switch machine through the clutch to be through the spring 15, it is provided that the driving torque of the clutch is maintained substantially constant as regulated by the compression of the spring l5. When a higher torque tends to be developed by the clutch as the speed increases the spring 'i5 is further compressed and thus decreases the pressure of the shoe el against the inside surface of the drum To consider the mode of operation of the machine in case the switch points are obstructed so that full operation of the track switch cannot be accomplished, it will be apparent from the above description, that slippage of the clutch takes place similar to that which has been described, and that such slippage continues until the pole changer ring 84 has been driven to its i full operated position to pole change the motor M and thus condition it for restoration of 'the switch machine to its former position when such position is designated by restoration of the switch control lever SML. In other words, in case an obstruction is encountered in the switch points, the clutch` slips until full operation 'is accomplished to pole change the motor M, and

the actuation of the lever SMLback'to itsformer position will cause the switchpoints` to vbe restored Because of there beingponly a partial stroke of restoration of the switch pointsunder V such conditions there is .clutch slippage'on the restoration stroke so as to actuate the pole changer ring 82 toits fully restored position and thus pole change the motorM. it will be there- -fore seen that under any condition'where only ...a-partial stroke is accomplished, a full stroke operation of the switch machine is accomplished by slippage of the clutch in order to condition .'the switch machine for reversal by the rotation 4ofthe pole changer ring 84.

F'There are conditions such as where'highfspeed Y ,train movements are to be made through'a track switch where it is more desirable to positively yflock both switch points and tie them together Arigidlywith a vfront rod, than to provide for trial- 4ability of the track switch without damage.

To meet these requirements, the power switch layout maybe provided as shownin Fig.` 5-wherein a front rod 120 is illustrated as connecting `the, `points 1S and 1l of the track switch, and a switch rod Y121 lis `provided for connecting the switch Vpoints 16 and- 1l together having a suitable connector basket 122 at its center point /for'connecting the single throw rod 123. The throw Ared '123 in turn is connected to the crank V`arm 33`of'the switchmachine. The'connecter "basket 122 'includes adjustable means whereby 'there'maybe `free travel of the throw rod 12S `to compensate 'for the differencein :the stroke'of 'the` switch machine from the' throw of the par- 'ticular track switch with which Athe switch machine is associated.

For the power switch layou-t'asr showninFig. 5, the switch machine is modified from the machine as it has been described by the-substitu- V `tion of a lock and detector mechanism DM for the supporting bracket 24 of Fig. l. This mechanism'DM acts upon a .lockrod l2!! connecting the 'mechanism with theiront rod 120 as shown yin 'Fig to lock vthe track switch'in itsY full normal Vand full reverseA operated positions, and a detector rod 125 is provided for connecting the detector mechanism `oi the switch machine with --the switch point 16, this rod 125 being secured to the switch point I6 byasuitable "lug of the type normally employed-in practice for this pur- 1 pose.

With reference to Fig.6, the 'lock and point detector mechanism DM `is illustrated as comprising a case C1 'whichis secured to the end of therswitch 'machine case Cby the bolts 12E, the

ca-se Cl being provided with a .base flange 12'1 hav-ing vholes 132-8 for securing of thecase C1 to 'the Vnumber vO tie, land thus providing an end support for the switch machine SM with which the vlock and detector mechanism VDM is-associated. The case 'CT has longitudinal Achannels formed therein along eachsidezandnear the bottom of .the case for the passage of respective normal and reverse lock Vplungers .129 and fltl'i'respectively .which are actuatedlongitudina'llyby the cam surface of the end plate 65 of theswitch machine which has been described as "being driven in .accordance with the rotation of the throw shaft.

'Each of lthe lock plungers 129 and 130 has v:formed on the sides thereof lugs Y131 (see Fig. 9) spaced .for receiving a rounded end 132a of a -crank ,'1'32 which is 7pivoted by 'the pin 133 mid- ,way-between 'the normaland reverse :lock plungers`1'29 and 13B. Thetwo cranks '1`32'areibiased Yrotatably opposite to each other by a compression spring 1313 which is disposed between lugs 1322 of the respective cranks 132 and suitably secured vby a bolt E35 extending through these flugs lzbandaxially through the center of the spring 13d. By this arrangement it is provided that each lock plunger 122 and 136 in turn is positively driven outwardly from the cam end plate (i5 by the vrotation of the end plate 65 for iun'locking the associated track switch from its respective normal and reverse locked positions, 'but the locking Vor" the switch is accomplished by the movement of a lock plunger inwardly toward thecam of the end plate 65 as driven through the `cranks 132 and through the compression spring 13d, thus permitting the rotation of the cam of the end plate to be completed for each switch operation, even though, through faulty adjustment of the lock rod 12d, or the associated track switch, the lock plunger may be surliciently out of alignment so that it may not be driven to `its full locking position. To facilitate smooth operation of the lock plungers in accordance with the rotation of the cam of the end plate '65, suitable rollers 135 are provided at the lower ends of the plungers 129 and ISU as viewed in Figs. 6 and 9 which bear against the cam of the end plate B5 and follow its contour as the switch machine is operated.

adjustment rod i which is longitudinally adiustable with respect to the lock rod 424 accordmg to the usual practice in lock rod adjustment lby the adjustment nuts 13S which are used in "securing the adjustment rod 138 to the lock rod 124. When the track switch is in its full normal position as shown, the reverse lock plunger 132 bears against the highest portion 65e of the cam of the end plate et, and is thus in a position where its locking dog Hit (see Fig. 8) has been withdrawn from the lock rod E24 and in a position urging the normal lock plunger 12S through the coupling of the cranks 132 and compression spring 134, against the lowest portion d of the cam of the end plate 65. The locking dog Idil as shown in Fig. '8 as being welded to the lower side of the reverse lock plunger i3d, but it is to be understood it could be otherwise secured, or it could be formed as integral with the plunger 13S. The lock plungers 129 and 13B) are maintained in their respective longitudinal channels 'by the top plates 141 which are secured to the case C1 by the screws 1&2.

To consider the mode of operation of the locking mechanism that has been dscribed, a typical operating condition will be assumed where the switch machine is driven to actuate its associated track switch from its normal to its reverse position. As has been described, the switch machine is illustrated as being in its normal locked position, and in this position the normal lock plunger 1291s retained in a position bearing against the end Plate 65 at the lowest portion of the cam of :the end plate so that the plunger E29 engages the locking notch 13'1 of the adjustment rod 138 which The lock is associated with the lock rod i.

13 plunger |29 is biased against the end plate 65 by the compression spring |34 acting through the respective cranks |32 which have been actuated about their pivot point |33 by the longitudinal operation of the reverse lock plunger |39, When the switch machine is in its normal position, the lock plunger |39 does not engage the lock rod |24 or the adjustment rod |38 in locking engagement because of the clearance slot |43 in the lower side of the lock plunger |30 as viewed in Fig. 8. It will be noted that this clearance slot is of sufficient length to permit the actuation of the reverse lock plunger |39 as required for the throw portion of the operating stroke so that this portion of the stroke is completed before the locking dog |59 of the lock plunger |39 starts to engage a locking notch in the lock rod |24.

Assuming power to be applied to the switch machine for operation to its reverse position, the

roller ist of the normal lock plunger |29 rides along the inclined surface 65e of the cam of the progresses from that point there is no further movement of the lock plungers |29 and |39 for the throw portion ofthe switch as the lock rod |24 is being actuated to the right and as the track switch moves from its normal to its reverse position.

Although the use of the compression spring |34 for coupling the cranks |32 would permit the disengaging of the lock plunger |29 from its locking position as has been described without relative opposing movement of the lock plunger |30, it is preferably provided that for the unlocking portion of the stroke, the vlock plunger |39 be permitted to ride downwardly on an inclined surface 65f which is the reverse of the inclined surface 55e which actuates the normal plunger |29. Thus after the track switch has been unlocked under the above described conditions, the lock plungers |29 and |39 are both held in disengaging positions, the lock plunger |29 bearing against the portion 55g of the cam of the end plate 65, and

the lock plunger |39 bearing against the surface 55h (see Fig. 4) of this cam.

Upon the completion of the throw portion of the operating cycle under consideration, the roller |39 of the lock plunger |29 starts to ride up the inclined surface 65z of the cam of the end plate 95, and the reverse lock plunger |39 is thus driven through the compression of spring |53?!v toward the end plate 65, and it follows a reverse inclined surface 65j (see Fig. 4) Thus as the reverse locking portion of the cycle of operation of the switch machine is completed, the lock plunger |29 is actuated to its fullest extended position and bears against the cam surface 55o of the cam of the end plate 55. At this time, the reverse lock plunger |39 has actuated its locking dog |50 within notch |44 of the lock rod 25| so as to lock the points of the associated track switch in their full reverse positions. The lock plunger |35 at this time bears against the lowest portion e501 of the cam of the end plate 65. It will be noted that if, for some reason, the locking notch IM of the lock rod |24 were not in proper alignment for the locking dog |45 to enter the notch |44, the operation of the switch mafio chine would be completed, and the lock plunger |29 would be actuated to its fully extended position, and the spring |34 would be further compressed because of the failure of the lock plunger |39 to complete its cycle of operation. Thus the operation of the track switch would be completed, but the point detector contacts would be held open as will be more readily apparent as the description progresses.

Having thus described specifically the mode of operation with respect to the locking of the lock rod |24 by the lock plungers |29 and |35 for the operation of the switch machine from its normal position to its reverse position, it is to be understood that the reverse of this mode of operation is accomplished when the switch machine is operated from its reverse to its normal position.

According to the embodiment of the invention illustrated in Fig. 5, a conventional detector rod is provided for actuation of a detector contact mechanism, rather than having the detector contact mechanism actuated off of the end plate 65 as has been illustrated in Figs. 2 and fi. Thus for the embodiment according to Fig, 5, the circuit controller that is illustrated in Figs. 2 and 4 as being actuated by the end plate G5 is not required,

and a detector mechanism as illustrated in Figs. 6 to 9 inclusive is substituted therefore.

With reference to Fig. 6, two stationary contact blocks of insulating material are oppositely disposed within case C1 and suitably secured to the case by the screws |55. These blocks |45 have secured thereto oppositely disposed contact springs le? which have associated therewith respective terminal posts |48 for the connection of wires of signal control circuits, and the like.

Disposed beneath the left hand contact block as viewed in Fig. 7, is a bracket |49 pivoted by the pin |58, and biased downwardly about this pivot point |5 by a compression spring |5l. This bracket |49 carries a cradle |52 which is pivoted by a pin 53 extending through the left hand end of the bracket |559 as viewed in Fig, 7 so as to locate the cradle |52 substantially at the center of the case C1, and disposed between the oppositely disposed contact springs I4?, The cradle |52 has a block |62 of insulated material secured at the top thereof, and this block |54 of insulating material carries respective contact strips |55 which are adapted to selectively close respective electrical circuits between adjoining pairs of contact springs lil which are secured to the stationary contact blocks |45. Thus one of these contact strips |55, as illustrated in Fig. '7, is arranged to engage adjoining contact springs |47 either at the left or at the right thereof as the cradle |52 is actuated counter clockwise and clockwise respectvely about the pivot point |53.

The detector rod 25 has an associated adjustment rod |54 provided for the purpose of obtaining adjustment in a manner comparable to that which has been described for the adjustment of the normal and reverse locking notches of the lock rod |25, the upper sides of the detector and detector adjustment rods |25 and |56 respectively being notched to govern the rocking of the cradle |52 about its pivot point |53, the cradle |52 being provided with rollers |55 and |51 which are biased against the upper surface of the detector rod |25 and the detector adjustment rod |541 so that they can enter the respective reprenez actuatedfast-is vthe-usual Apractice iin 'switch ma- Vchimes of :this character, by .the lock ,plungers VI 29 :and Vthat circuits through the respective :ad-

joining pairs of contact springs |141 .can lbe ,said to check `the mechanism of 4the'sw'itch machine inicorres?ondence with the switch points. -lhis'is accomplished 'by the rollers |58 (see Fig. v'7) at *controller is maintained on center, with all conv tacts are Yopened in accordance with the movement ofthe cradle .engaging dog |59 as the lock plunger |29 is actuated outwardly by the roller 35 riding along the inclined surface 55e of the Having thus described one specific embodiment or the present invention, together `with cer- -tain:inodii'ications, as applied to the control of specific track switches, it is desired to be understood .that the form shown has been shown and described more for the purpose of illustrating the principles and inode of operation involved than :for indicating the scope of the present invention, .and it is to be further understood that various other modifications, adaptations and alterations may be applied to the specific form shown within the scope of the present invention, except as limited by the appending claims.

What claim is:

Y1. A track switch layout comprising in combination, a pair of movable switch points, a power switch machine having a throw shaft, respective normal and reverse crank arms rotatively secured on said throw shaft and displaced from each other by a substantial angle, and a pair of throw rods connecting the respective crank arms and switch points, one of said throw rods being `effective to connect said normal crank. arm vwith one .movable switch point, and the other throw rod being effective to connect the Vreverse crank arm with the other switch point, and said throw rods having their ends for attachment to said crank arms formed as a hook and adapted to hock around respective fixed points of said switch machine when their associated vswitch points are closed.

2. VAtrack switch layout comprising in combination, a pair of Vmovable switch points, a power switch machine having a throw shrft with two angularly displaced cranks rotatively secured thereto, throw rods connecting the respective cranks and switch points, each of said throw rods being formed as a hook near its end connected to its associated crank, said hook being adapted to hook around a fixed point of said switch machine when the associated switch point is closed and thereby lock the switch point in its closed position.

3. A track switch'glayout comprising in comzbinaton, a .pair voi movable switch points, a

#power switch -maohine Vhaving .a throw shaft with two angularly displaced-cranks rotatively secured thereto, throw rods Vconnecting the respective cranks and the switch points, each of said throw :rods being formed 'as a hook near its end connected toits associated crank, said hooks being adapted to hook around a fixed point of said switch Ymachine only when the associated switch point `is closed, and said cranks being so disposed on saidV throw shaft that a force urging the opening of yan `associated closed switch point if applied rt that switch point urges the hook of the `associated rthrow rod in a direction to maintain its locked position.

Y' 4. Ina track switch layout, a pair of movable switch points, a power vswitch machine having a throw shaft with two angularly displaced cranks rotrtively secured thereto, throw rods connecting the respective cranks and the switch points, one of said throw rodshaving its end for attach- Yment to its associated crank formed as a hook whereby that rod is hooked around the underside of `said throw shaft when the associated switch point is closed to lock that switch point in its closed position.

5. In a track leyOut, the combination with a pair of movable switch points of a power switch machine having a throw shaft with two angularly displaced cranks rotatively secured thereto, throw -rods Vconnecting the respective cranks and the switch points, one of said throw rods having a hook formed nerr its end for attachment to its associated crank Vwhereby the associated switch point is locked bythe hooking of that throw rod around a fixed point of said switch machine when the associated switch point is closed, whereby by the angular displacement of said cranks, the crank connected to a movable switch point that is open can rbe actuated 'by the crowding of that switch point during the trailing movement of a mobile unit to unhook the other throw rod from its locked position and thereby permitting a trailing movement through the track switch without -whereby said throw shaft is driven in one direction or the other by reason of one or the other of said'detents being driven against one end or the other of said slot in said plate.

7. A `switch machine for the power operation of a track switch comprising, a motor driven drum, a circular friction band within said drum having transverse detents extending from respective open ends thereof. a throw shaft extending through said drum along the axis thereof, spring biasing means normally expanding said ends of said friction band to cause it to beer against the inner surface of said drum, a plate rotatively secured to said throw shaft, said plate having an angular slot formed therein for receiving said detents and thereby causing said contacton and a .cam .on'said drum for actuating said contactor at respective normal and reverse operated positions.

8. A switch machine for the power operation of a track switch comprising a motor driven drum, a circular friction band inside said drum, spring biasing means for maintaining said friction band in contact with said drum, a throw shaft extending through said drum along its axis, a plate rotatively connecting said friction band and said throw shaft, a detector contactor and a pole changing contacter, a cam rotatively driven by said drum for actuating said pole changing contactor, and a cam rotatively driven by said throw shaft for actuating said detector contactor.

9. In a power switch machine for operating the movable points of a track switch, a clutch comprising a motor driven drum and a circular friction rshoe bearing against the inner side of said drum, a throw shaft extending longitudinally along the axis of said drum and through the center thereof, a disc coupling said throw shaft and said friction shoe, a rotary cam plate secured at one end of said throw shaft, a lock rod extending transversely through said switch machine, and normal and reverse laterally spaced lock plungers traversing said lock rod and having their ends bearing against said cam plate so as to be actuated thereby to selectively lock said lock rod in respective normal and reverse operated positions of the throw shaft.

10. A track switch layout comprising in combination, a pair of movable switch points, a clutch having a motor driven drum and a circular friction shoe bearing against the inner side of said drum, a throw shaft extending along the axis of said drum and through the center thereof, means for coupling said throw shaft to said friction shoe, respective normal and reverse crank arms rotatively secured on said throw shaft and displaced from each other by a substantial angle, and a pair of throw rods connecting the respective crank arms and' switch points, one of said throw rods being effective to connect said normal crank arm with one movable switch point, and the other throw rod being effective to connect the reverse crank arm with the other switch point, and at least one of said throw rods having its end attachment to its associated crank arm formed as hook and adapted to hook around a fixed point when its associated switch point is closed.

11. A power switch machine for operating the movable points of a track switch comprising in combination, a clutch having a motor driven drum and a circular friction shoe bearing against the inner side of said drum, a throw shaft extending along the axis of said drum and through the center thereof, means for coupling said throw shaft with said friction shoe, a rotary cam plate secured at one end of said throw shaft, a lock rod extending transversely through said switch machine, normal and reverse lock plungers traversing said lock rod and having their ends bearing against said cam plate so as to be actuated thereby to selectively lock said lock rod in respective normal and reverse operated positions of the switch machine, a detector rod extending transversely through said switch machine, and a point detector contact mechanism having contacts closed only when said lock plungers and said detector rods are actuated to predetermined corresponding normal and reverse positions.

12. A power switch machine for operating the movable points of a track switch comprising in combination, a clutch having a motor driven drum and a circular friction shoe bearing against the inner side of said drum, a throw shaft extending along the axis of said drum and through the center thereof, means for coupling said throw shaft and said friction shoe, a rotary cam plate driven by said throw shaft, a lock rod extending transversely through the switch machine, respective normal and reverse laterally spaced lock plungers traversing said lock rod and bearing against said cam plate, and reciprocating linkage connecting said lock plungers for actuating each lock plunger in one direction longitudinally to lock said lock rod in response to the actuation of the other lock plunger longitudinally in the direction by said cam plate.

13. A power switch machine for operating the movable points of a track switch comprising in combination, a clutch having a motor driven ldrum and a circular friction shoe bearing against the inner side of said drum, a throw shaft extending longitudinally along the axis of said drum, means for coupling said throw shaft and said friction shoe, a rotary cam plate driven by said throw shaft, respective normal and reverse laterally spaced lock plungers bearing against said cam plate and traversing said lock rod, and a spring biased linkage coupling said lock plungers so that the driving of one lock plunger longitudinally by said cam drives the other lock plunger in the opposite direction through said spring linkage to lock said lock rod.

NED C'. L. BROWN.

References Cited in the le of this patent UNITED STATES PATENTS Number Name Date 1,695,900 Powell Dec. 18, 1928 1,699,716 Reynolds et al Jan. 22, 1929 2,082,133 Wyant June 1, 1937 2,124,739 Kershaw July 26, 1938 2,320,171 Bone May 25, 1943 

